I just finished watching an interesting episode of Star Trek: Voyager, "Nothing Human." In this episode, the life of a Voyager crewmember depends on the research of a man who is revealed to be a war criminal. Essentially, he's the Star Trek equivalent of the Nazi doctors who performed experiments on the concentration camp victims as part of their research. (In "Nothing Human," this research was to search for a cure, not to develop new methods of killing Jews or something that's 100% sinister.) The episode had very little in the way of plot, really (you don't know he's evil at the beginning)—the episode mostly just revolved around the opinions of the different crew members regarding whether or not it was moral to accept a treatment that was developed through torture. In the episode, it boiled down to two sides: the doctor killed thousands to save millions... and potentially one more. To use an accounting term, those peoples' lives are already a sunk cost, right? But, accepting treatment is, in a way, validating the work of a mass murderer. It's an interesting moral dilemma that I never really thought about before.
Anyway, if you want to see how it ends, you can follow the episode synopsis link I provided earlier. But, like a lot of episodes, the plot and the outcome weren't that important, just the issues raised, conveniently oversimplified into 44 minutes. I was entertained.